Sandy Johnson (Judith Myers) posed fully nude for Playboy before getting into acting. She said in a rare interview in 2018 that she did it to earn money to help her dad who had cancer. Her willingness to go nude is how she got cast in the five films she made in her career (three in 1978 and two in 1979). Except for the horror film Halloween (1978), all were teen sex comedies, including Surfer Girls. She appeared nude in every film and then left the business.
Sandy Johnson described the shooting as an uncomfortable experience due to the filmmakers' insistence to push the sexually explicit material and she wasn't comfortable with it.